Aysen Yarat

Resveratrol treatment protects against doxorubicin-induced cardiotoxicity by alleviating oxidative damage.

The possible protective effects of resveratrol (RVT) against cardiotoxicity were investigated in Wistar albino rats treated with saline, saline+doxorubicin (DOX; 20 mg/kg) or RVT (10 mg/kg)+DOX. Blood pressure and heart rate were recorded on the 1st week and on the 7th week, while cardiomyopathy was assessed using transthoracic echocardiography before the rats were decapitated. DOX-induced cardiotoxicity resulted in decreased blood pressure and heart rate, but lactate dehydrogenase, creatine phosphokinase, total cholesterol, triglyceride, aspartate aminotransferase and 8-OHdG levels were increased in plasma. Moreover, DOX caused a significant decrease in plasma total antioxidant capacity along with a reduction in cardiac superoxide dismutase, catalase and Na+,K+-ATPase activities and glutathione contents, while malondialdehyde, myelopreoxidase activity and the generation of reactive oxygen species were increased in the cardiac tissue. On the other hand, RVT markedly ameliorated the severity of cardiac dysfunction, while all oxidant responses were prevented; implicating that RVT may be of therapeutic use in preventing oxidative stress due to DOX toxicity.

Resveratrol improves cardiovascular function and reduces oxidative organ damage in the renal, cardiovascular and cerebral tissues of two-kidney, one-clip hypertensive rats

Objectives  The putative protective effects of resveratrol against oxidative injury in the heart, kidney and brain tissues of rats induced with the two‐kidney, one‐clip (2K1C) hypertension model were investigated.

Melatonin improves cardiovascular function and ameliorates renal, cardiac and cerebral damage in rats with renovascular hypertension

Abstract:  The effect of melatonin was investigated in an angiotensin II‐dependent renovascular hypertension model in Wistar albino rats by placing a renal artery clip (two‐kidney, one‐clip; 2K1C), while sham rats did not have clip placement. Starting either on the operation day or 3 wk after the operation, the rats received melatonin (10 mg/kg/day) or vehicle for the following 6 wk. At the end of the nineth week, after blood pressure (BP) and echocardiographic recordings were obtained, plasma samples were obtained to assay lactate dehydrogenase (LDH), creatine kinase (CK), antioxidant capacity (AOC), asymmetric dimethylarginine (ADMA), and nitric oxide (NOx) levels. In the kidney, heart and brain tissues, malondialdehyde (MDA) and glutathione (GSH) levels, superoxide dismutase (SOD), catalase (CAT), myeloperoxidase (MPO) and Na+‐K+ ATPase activities were determined. 2K1C caused an increase in BP and left ventricular (LV) dysfunction. In hypertensive animals LDH, CK, ADMA levels were increased in plasma with a concomitant reduction in AOC and NOx. Moreover, hypertension caused a significant decrease in tissue SOD, CAT, and Na+, K+‐ATPase activities and glutathione content, while MDA levels and MPO activity were increased in all studied tissues. On the other hand, both melatonin regimens significantly reduced BP, alleviated oxidative injury and improved LV function. In conclusion, melatonin protected against renovascular hypertension‐induced tissue damage and improved cardiac function presumably due to both its direct antioxidant and receptor‐dependent actions, suggesting that melatonin may be of therapeutic use in preventing oxidative stress due to hypertension.

Tissue factor activities of streptozotocin induced diabetic rat tissues and the effect of peanut consumption.

Tissue factor (TF) is considered to be a major regulator of normal haemostasis and thrombosis. Circulating TF activity is suggested to be associated with diabetes mellitus. Various tissues and body fluids have TF activity. The aim of the present study was to investigate the TF activity of streptozotocin (STZ) induced diabetic rat tissues. Peanut consumption is reported to be associated with decreased risk of type 2 diabetes. Therefore, the effect of peanut consumption on the TF activity of STZ induced diabetic rat tissues, and haemostatic parameters such as protrombin time (PT), activated partial thromboplastin time (APTT) and fibrinogen levels were determined.

Association between dental-oral health in young adults and salivary glutathione, lipid peroxidation and sialic acid levels and carbonic anhydrase activity

The aim of the present study was to evaluate the relationship between salivary oxidative stress and dental-oral health. Healthy young adults, matched for gender and age, with (N = 21, 10 men, mean age: 20.3 +/- 1 years) and without (N = 16, 8 men, mean age: 21.2 +/- 1.8 years) caries were included in this study. The World Health Organization (WHO) caries diagnostic criteria were used for determining the decayed, missing, filled teeth (DMFT) index. The oral hygiene and gingival status were assessed using the simplified oral hygiene index and gingival index, respectively. Unstimulated salivary total protein, glutathione (GSH), lipid peroxidation and total sialic acid levels, carbonic anhydrase activity, and salivary buffering capacity were determined by standard methods. Furthermore, salivary pH was measured with pH paper and salivary flow rate was calculated. Simplified oral hygiene index and gingival index were not significantly different between groups but DMFT scores were significant (P < 0.01). Only, GSH values were significantly different (P < 0.05) between groups (2.2 and 1.6 mg/g protein in young adults without caries and with caries, respectively). There was a significant negative correlation between DMFT and GSH (r = -0.391; P < 0.05; Pearsons correlation coefficient). Our results suggest that there is an association between caries history and salivary GSH levels.

Fluoride levels in various black tea, herbal and fruit infusions consumed in Turkey

The fluoride contents were determined by ion-selective electrode in 26 black tea samples originally produced in Turkey, Sri Lanka, India and Kenya, and in 14 herbal and seven fruit infusions originated from Turkey. Fluoride content in black tea infusions ranged from 0.57 to 3.72 mg/L after 5 min of brewing. Higher fluoride levels were found in black teas originated from Turkey when compared with teas originated from Sri Lanka. Moreover higher fluoride levels were determined in black tea bags compared with granular and stick-shaped black teas. However, herbal and fruit infusions were characterized by low values of fluoride (0.02-0.04 mg/L) after 5 min of brewing and increasing brewing time to 10 min caused only slight increases in some infusions. As a result, consuming tea infusions prepared from some black tea available in Turkish market, especially black tea bags, in large quantities may lead to exposion to a high amount of fluoride which may cause dental fluorosis. Although fruit and herbal infusions are safer to consume their fluoride contents are too low for caries prevention. In countries such as Turkey where tea is traditionally consumed, the fluoride concentration and daily safety precautions should be indicated on tea products.

Effect of parsley (Petroselinum crispum) on the skin of STZ induced diabetic rats.

Parsley (Petroselinum crispum) is one of the medicinal herbs used by diabetics in Turkey and it has been reported to reduce blood glucose. The purpose of this study therefore was to investigate the effect of feeding parsley on diabetes induced impairments in rat skins. Uncontrolled induced diabetes caused significant increases in nonenzymatic glycosylation of skin proteins, lipid peroxidation and blood glucose. Administration of parsley extract did not inhibit these effects except for the increase in blood glucose. SDS‐polyacrylamide gel electrophoresis revealed no significant differences in any protein bands between any of the groups. Copyright

Serum nickel levels of diabetic patients and healthy controls by AAS with a graphite furnace

In this study, serum nickel levels of diabetic patients and healthy controls were determined by AAS with a graphite furnace. The serum nickel concentrations were found to be 1.15±1.89 μg/L in healthy controls and 0.82±0.74 μg/L in diabetics. There was, however, no statistically significant difference between the two groups (p=0.13). The relationship of nickel levels to diabetes type and duration, diabetic complications and treatment, sex, age, and heredity was investigated. However, again no significant differences were found, nor was there any correlation between serum nickel levels and blood sugar, HbA1c, fructoseamine, sialic acid levels, and age.

Characterization of the secretome of human tooth germ stem cells (hTGSCs) reveals neuro-protection by fine-tuning micro-environment

Bone-marrow-derived mesenchymal stem cells (MSCs) demonstrate neuro-protective effects in several disease models. By producing growth-factors, cytokines and chemokines, they promote survival of neurons in damaged brain areas. Alternative MSC sources, such as human tooth germ stem cells (hTGSCs), have been investigated for their neuro-protective properties. They ameliorate effects of neuro-toxic agents by paracrine mechanisms, however these secreted bio-active molecules are not yet characterized. Therefore, the current study aimed to provide a detailed analysis of the secretome of hTGSCs. Brain cells were exposed to various toxic materials, including Alzheimers β-amyloid peptide (β-AP) and 6-hydroxy-dopamine (6-OHDA). When co-cultured with hTGSCs, the activity of a number of anti-oxidant enzymes (catalase, glutathione-s-transferase, glutathione-peroxidase, superoxide-dismutase) was increased and neuronal death/apoptosis was subsequently reduced. The composition of the secreted bio-active materials is influenced by various pre-existing factors such as oxygen and glucose deprivation and the age of cells (passage number). This report reveals for the first time that the neuro-protective secretome of hTGSCs and the micro-environment of cells have a mutual and dynamic impact on one another.

Effects of Ankaferd Blood Stopper and Celox on the Tissue Factor Activities of Warfarin-Treated Rats

The aim of this study is to evaluate the effect of these new generation hemostatic agents on early-stage soft tissue healing of warfarin-treated rats by measuring the tissue factor (TF) activities. Rats in the warfarin group were treated intraperitonally with 0.1 mg/kg warfarin, and rats in the control group were treated with 1 mL/kg saline. All rats had 3 incisions on dorsal dermal tissue applied Celox, Ankaferd Blood Stopper (ABS), or no hemostatic agent. Six rats from each group were killed on day 4, and the other 6 were killed on day 8. Prothrombin time (PT) and TF activities were evaluated, respectively. Both the hemostatic agents positively affected the hemostasis. Warfarin treatment increased the PT levels as expected. Celox-treated dermal tissues had higher TF activity when compared to ABS-treated ones. The ABS affected the early-stage healing positively in clinical aspect, whereas Celox was more effective on hemostasis by means of increasing TF activities.